I agree with a previous poster. If you call the duty planner at your local office you will be able to find out whether there have been planning applications in the past. Whether any are pending and the outcome. I don't think specifically that plans can be restricted as such, they are either granted or not. Since the time that this question was written there has been a massive relaxation of planning laws. Many building procedures now do not need planning permission at all under permitted development rules. It might be an idea to look at the PD rules before taking on the expense and uncertainty of a planning application.